Slowridr

Have a question on how the Smoothie size 58 compares to the Supersix size 56? I am most worried about reach and how different they are. I know the smoothie 58 is almost 1 cm longer in effective top tube. But does the seat angle and head tube angle play a role? Any other big differences. Im mostly concerned if the smoothie will be to long. I know the head tube is longer on the smoothie. What role will adding a headset play on that.

I am asking because I currently have a supersix, and have an opportunity to get a deal on the smoothing 58. Just wanted to make sure I can get roughly the same setup between the 2 sizes by playing around with the stem. The fact the head tube is longer on the smoothie is probably a good thing as I run spacers on my supersix.

Thanks

tangerineowl

Frames are very similar. No need to worry about reach; there's only 1mm diff.

Depending on where your seatpost currently clamps on the Supersix's rails, the worst that would happen is you'd have to get a zero-setback post to run on the Smoothie.

Like you mentioned, you're already running a few spacers on the Supersix, so you'd have minimal (perhaps 5mm) on the Smoothie.
Any further front end tweaks can also be sorted by using a lower stem.
There are headsets out there which have a lower stack height than normal, but I don't think you'd have to go there.